Task 5: Conduct Risk Assessment

Steps to Conduct a Risk Assessment

The desired consequences of the steps to conduct assessment are:
• Appraisal of the potential impact of each disaster on the community people, natural environments, structures, and economy in the planning jurisdiction.
• An understanding of the most critical risks and overall susceptibility of each community.

The planning team can use the above information regarding the overall susceptibility and potential impacts to develop problem statements and recognize mitigation activities to diminish risk.

For mitigation planning efforts in multi-jurisdictions, the risk appraisal should lead to an assessment of overall susceptibility and potential impacts that each involved jurisdiction will employ to develop specific mitigation activities. In a multi-jurisdictional plan, vulnerabilities, assets, and overall risk must be addressed since these are unique to each community. Hazards and threats may be explained for the whole planning jurisdiction, but the mitigation plan should also clarify any risk hazards that are unique to or diverse within communities.

An update of the existing mitigation plan should focus on the risk changes, specifically changes related to new hazard information and land use development, since the previous plan was already implemented. Examples of information, such as areas affected by recent disasters, the latest development in hazard-prone regions, and new data or reports, should be incorporated into the hazard plan to evaluate the current risk and revise problem statements.

Contact the local community for specific information on past impacts and community assets. The State Hazard Mitigation Plan and your SHMO (State Hazard Mitigation Officer) can also provide information on hazard data and risk assessment.

The Washington Riskscape Atlas provides comprehensive information about various critical infrastructure facilities within your jurisdiction.Link to Atlas

Element B1: For mitigation planning efforts in multi-jurisdictions, the risk appraisal section must evaluate the risks of each jurisdiction varying from the risks faced by the whole planning area. 44 CFR §201.6(c)(2)(iii)

Following are the proven steps to conduct a risk assessment:

Step 1: Describe Hazards

The mitigation plan should describe the natural hazards or threats that affect the jurisdiction(s) in the planning region. Following are some suggestions to recognize natural hazards:
• Gain information on hazards affecting your planning area by evaluating your State Hazard Mitigation Plan.
• Include the disaster declaration history in the hazard plan.
• Browse online resources, for example, the National Climatic Data Center to download weather-related events.
• Appraise current reports, studies, and plans associated with hazards in the planning region. You can get good hazard-related information from the state and federal agencies.
• Make use of FIRM (flood insurance rate maps) and non-regulatory flood risk evaluation products developed by FEMA for your community as part of the NFIP (National Flood Insurance Program) and the RiskMAP program.
• Get in touch with universities or colleges that have academic programs or extension services related to hazards and risks.
• Discuss with the stakeholders and your planning team about the types of hazards affecting the planning region.
• For information on past disaster occurrences, contact local resources such as newspapers, local historical society, chamber of commerce, or other resources.
• To update the existing plan, refer to previously recognized hazards and evaluate their current relevance.

If your community’s mitigation plan skips a natural hazard that is known to frequently affect the planning region, the plan should explain the planning team’s justification for skipping it. For instance, the magnitude and likelihood of a possible hazard are so minimal that the planning team chose not to carry out the risk assessment or give an in-depth description.

Element B1: The risk appraisal must describe the extent, location, and type of all-natural hazards that can have an effect on the jurisdiction. 44 CFR §201.6(c)(2)(i)

Describing Hazards

The risk assessment, for each planning area affected by the hazard, should describe the extent, location, previous occurrences, and likelihood of future hazard events. Any other recognized hazards, any newly available data including new flood studies, and all hazard events that took place since the last plan was implemented should be incorporated in the plan updates.

Location: It means the geographic regions inside the planning area that are prone to hazard, for example, a floodplain. Hazard-prone regions may also be defined as low wildfire hazard regions Vs high wildfire hazard regions. Hazards like winter storm or drought may evenly affect the whole planning region. There are several formats to describe the location for many hazards, such as a narrative, but the best way to illustrate any location is through the use of maps.

Extent: It stands for the magnitude and strength of the hazard. Depending on the hazard, the extent can be explained in a number of following ways:
• The value on a recognized measurement system or scientific scale, for example, 5.5 on the Richter Scale (for earthquakes) or EF2 on the Enhanced Fujita Scale (for tornadoes).
• Other magnitude measures like wind speed or water depth.
• The onset speed, for instance, earthquakes take place without warning whereas there are longer warning periods in case of hurricanes, which allow governments and people more time to get ready and evacuate.
• Extent also depends on the duration. The longer the hazard duration event, the greater the extent. For example, flooding that peaks and remains in place for days is more damaging than the flooding of the same depth that retreats in a matter of hours.

There is a big difference between describing the extent of a hazard and explaining its potential impacts on a community. Extent describes the hazard traits irrespective of the assets or people it affects, whereas impact explains how hazard affects the people and community assets.

Prior occurrences: The mitigation plan should document the history of previous hazard occurrences for each risk. This can help estimate the probability of future occurrences and forecast potential impacts. It may be useful to compile past occurrences for certain hazards. With the available data, it’s easy to describe the extent of the hazard events and its impacts, for example, injuries and fatalities, damage to building and infrastructure, and loss of life. To anticipate the potential impact of future hazard events, it’s better to understand the extent and impacts of the past hazard occurrences.

Element B2: The risk appraisal must document information on prior occurrences of hazard events and the likelihood of future occurrences of the hazard events. 44 CFR §201.6(c)(2)(i)

Likelihood of future hazard events: This information can be defined in a number of ways including the use of statistical probabilities or historical frequencies. Statistical probabilities typically refer to the hazard events of particular strength or size. The probability of a flood event of a specified size is described by the percent chance in a single year, for example, a 100-year flood or the one-percent annual chance of flood. The probability of hazard can also be evaluated using general rankings or narratives. If you use general narratives, these should be clearly documented in the plan. For instance, a hazard occurring every 1 to 10 years could be termed as “highly likely”, a hazard occurring every 10 to 50 years could be termed as “likely”, and a hazard occurring at intervals greater than 50 years could be termed as “unlikely”. Certain hazards occur almost certainly during a specific time of the year and some hazards can occur at any time of the year. For instance, flooding might be more common during the springs in the West due to snow melting, or during fall or late summer during the hurricane season in the East.

Climate Change

A discussion of the impacts of climate change can be included in the risk assessment by the planning team. This can give a better understanding of how risk changes may happen in the future, although as per the Federal mitigation planning directive this isn’t needed. While climate change in itself may not pose a risk or be a hazard, it has the ability to change the hazard traits that are presently affecting the planning region, for instance, climate change may result in more intense and frequent storms. Climate change can be included by the planning team in the mitigation plan as a separate section or the current hazards descriptions, for example, severe flooding, storms, drought, and wildfire. Strategies for climate adaptation that requires natural or human systems adjustments to mitigate the impacts of climate change may complement the strategies for other hazard mitigation. To get an overview of potential climate changes in your area, you can review various special reports published by Climate Impacts Group.

Climate Change and Climate Adaptation:
• Climate Change: It symbolizes a variation that is statistically important in either the mean state of the climate or in its unpredictability, continuing for an extended period (for decades or even longer). Climate change may occur due to external forcing or natural internal processes, or constant anthropogenic changes in land use or the composition of the atmosphere.
• Climate Change Adaptation: This stands for the modification in natural or human systems in response to the real or predictable climatic stimuli or their consequences.

Human-Caused Hazards and Technological Threats

Although not required as per the federal regulations, human-caused hazards and technological threats may be included in the mitigation plan by the planning team. Technological risks occur due to accidents or the failure of structures or systems, for example, airplane accidents or spilling of hazardous materials. Human-caused hazards occur due to deliberate sabotage actions of an adversary, for instance, a cyber or chemical attack. THIRA (Threat and Hazard Identification and Risk Assessment) describe the current hazard recognition and risk appraisal of a community mitigation plan; gives an all-inclusive approach to assess risks and related impacts with all sorts of hazards or threats; and acknowledges a method to evaluate a wider range of capabilities for mitigation, protection, response and recovery, and prevention.
For more information and suggestions on the types of hazards and threats in the mitigation plan, see Integrating Manmade Hazards into Mitigation Planning (FEMA 386-7)6.

Step 2: Identify Community Assets

Each participating jurisdiction needs to recognize the community assets at risk from hazards and disasters. Community assets are broadly described to include all the things that are important for the functioning of a community. Community assets are generally described in the following categories:
• People
• Economy
• Built environment
• Natural environment

Although hazards can affect all community assets, certain assets are more susceptible due to their physical traits or socio-economic utilities. An asset inventory serves the purpose of recognizing certain susceptible assets in your community. For the mitigation plan update, the asset inventory will be updated by the planning team to reflect existing conditions.


The most important asset of any community is its people. The risk assessment should identify areas of greater population density as well as populations that may have unique vulnerabilities. Most hazard mitigation plans focus on physical vulnerability, that is, the risks hazards posed to structures such as houses, apartments, schools, hospitals, and infrastructure. However, certain populations or groups may be especially vulnerable to disasters due to age, poverty, race, physical disability, or language barriers. These socially vulnerable populations often face greater challenges when preparing for, coping with, and recovering from disasters. Hazard mitigation plans should address both physical and social vulnerabilities.

In addition, visiting populations might also be at greater risk, for example, visiting students, visitors for special events, migrant farm-workers, and second homeowners. Visitors may visit special events such as large festivals or sporting events where people in huge numbers gather and become susceptible to threats and hazards. They may be less familiar with the local surroundings and threats, and ill-prepared to defend themselves against a hazard event.

The risk assessment should identify locations that provide health or social services that are critical to post-disaster response or recovery capabilities, including locations and support service operations for vulnerable populations (e.g., hospitals, dependent care facilities, oxygen delivery, and accessible transportation).
You can collect information on population from a variety of data sources, such as the U.S. Bureau of Labor Statistics, state population estimates, and the U.S. Census. Using maps to exhibit facilities that accommodate dependent populations or sites that host large groups of people can help display the relationship between population and impending hazards.

People (description)
• To assess potential risks, recognize the visiting population’s types and their most preferred locations.
• Recognize concentrations of community people to help achieve vigilance, response, and carry out mitigation activities.
• Recognize locations that offer health or social services critical to recovery fr0m disaster events.
• To forecast vulnerability, mull over demographics of estimated population growth.
• To develop best mitigation actions, recognize populations with functional needs, as well as locations and concentrations of access.


It’s economic resilience that drives recovery post-disaster. During the development phase of the mitigation plan, it’s very important to recognize those specific economic drivers that every community has, in order to diminish the hazard impacts on the community’s economy. Economic drivers can be documented with regard to direct or indirect losses. An example of direct loss would be inventory or building damage. An indirect loss would be the loss of employment wages and functional downtime that can be analyzed. Other than the community’s primary economic sectors such as service, agricultural, or manufacturing sectors, the local economy is also supported by commercial centers and major employers.

Economy (description)
• Recognize key economic sectors (like agriculture), major employers, and commercial centers whose inability to function or losses due to natural disasters would severely impact the ability of your community to recover from any hazard event.
• Evaluate the inter-dependency of businesses and economic sectors, as well as the infrastructure required to support them.

Built Environment

Examples of the built environment are existing structures, infrastructure, critical facilities, and cultural resources. When evaluating the built environment, consider important components such as areas of future growth and development.

1.) Existing Structures: Although the majority of structures are prone to risks, some buildings are more susceptible due to their age, use, location, condition, or construction type. Check with your local planning department and tax assessor to gain information on the ownership, land use, parcel boundaries, zoning, types, and numbers of structures.

Existing Structures (description)
• Recognize building types including industrial, commercial, and residential (single and multi-family).
• Verify the structure’s age and construction type to comprehend the quality of construction and building codes in force.

2.) Infrastructure: Infrastructure systems, such as power, transportation, wastewater, and communication, are crucial for the economic viability and life safety of any community. Infrastructure is also important for the functioning of several critical facilities, such as hospitals that constantly require water, electricity, and sewer to treat patients. Besides these critical facilities, the continuous operations of infrastructure systems are key factors in the impact of severity and recovery speed, during and post a disaster event.

3.) Critical facilities: These symbolize institutions and structures that are essential for the response of your community to hazards, as well as its recovery from disasters. Such facilities need to continue to function, during and post a disaster event, to diminish the impact severity and speed up recovery. When the planning team recognizes vulnerabilities, both the content value and structural reliability of critical facilities should be considered along with the consequences of disrupting their services to the community.

Infrastructure and Critical Facilities (description)
• Create a list of the site, age, life expectancy, and construction standards of the particular infrastructure, as well as all the specific critical facilities in the planning region.
• Evaluate inter-dependencies between the community people, critical facilities, and infrastructure systems.

4.) Cultural resources: These include unique or irreplaceable community assets that are both historic and cultural, for example, museums, concert halls, unique geological sites, stadiums, parks etc.

5.) Future development: To diminish future losses due to disaster events, the most effective way would be to disallow development in the hazard-prone areas and to enforce the expansion of critical structures in the safer areas. From the beginning of the community development, keep buildings, businesses, and people away from the hazard-prone areas. To ensure safe development, the mitigation plan should give a general narrative of community development trends and land uses, to allow the mitigation options to be taken into account in future land use assessments. The community’s master plans may have information on build-out environments and future land use.

Future Development (description)
• Recognize regions zoned and planned for annexation and future development.
• Recognize sites, types, and numbers of structures of intended new development and redevelopment.
• Appraise plans for new infrastructure, critical facilities, and other developments, such as storm-water management, to support current and future development.

Natural Environment

Natural resources and environmental assets are important to the uniqueness and quality of life of a community. These also support the community’s economy through tourism, agriculture, recreation, and various other ecosystem services like clean water and air. The natural environment also offers protective purposes that diminish the impacts of hazards and boost hazard-resiliency. For example, riparian regions and wetlands help soak up flood-waters; vegetation helps control erosion and lessens overflow; and landscaping help manage storm-water. Protection of environmental assets may provide opportunities to fulfill the objectives of the mitigation plan and other community goals, for example, contributing to the community’s economy, developing trails and parks, or protecting the vulnerable environment.

Natural Environment (description)
• Recognize the most valuable regions that can offer protective purposes to lessen the impact of hazard events.
• Recognize important habitat regions and other ecological elements that need to be protected.

Step 3: Risk Analysis

This process involves analyzing vulnerable assets, calculating each hazard’s losses, and documenting looming impacts. The rationale of risk analysis is to help people comprehend the planning region’s greatest risks. This process takes place after the recognition of vulnerable community assets and potential hazards.

The risk analysis techniques include scenario analysis, historical analysis, and exposure analysis. All these can be stated qualitatively or quantitatively. Quantitative assessments measure the potential losses and allocate values to the community assets at risk. Qualitative assessments explain the impact types that may take place during a hazard event. Such assessments can be conducted by the planning team, community members, stakeholders, and subject matter experts by discussing and brainstorming potential impacts.

Element B3: The risk analysis must describe an overall review of each hazard and its potential impact on your community. 44 CFR §201.6(c)(2)(ii)

1.) Exposure Analysis: This process recognizes the present and future community assets, located in hazard-prone areas, by using maps for visualization and GIS for evaluation. The scale of the hazard can also be taken into account, for example, community assets located in different flood frequency zones or assets located in low, medium, or high wildfire hazard regions.

Exposure analysis can help calculate the value, type, and the number of infrastructures, critical facilities, and structures, located in hazard-prone regions, in addition to the community assets prone to several disasters. This process can also be used to calculate the number of future infrastructures, critical facilities, and structures possible in the hazard-prone zones depending on the existing zoning and structure codes.

2.) Historical Analysis: This process uses data on losses and impacts from the prior hazard events to forecast potential impacts and losses, in case a similar event occurs in the future. Historical analysis can be particularly useful to predict hazards related to weather, for instance, drought, hail, and severe winter storms. The frequency of such events increases the likelihood of the communities to have information on and experience with hazard impacts and losses. In the case of recent hazard events, think not only about what was lost, but also about what could have been damaged if the impact was of a greater scale. In the case of not-so-frequent hazard events, mull over new development and infrastructure that may prove to be susceptible to a similar hazard event.
The mitigation plan must document structures insured by NFIP that have been damaged repeatedly by floods. Your State NFIP coordinator or local floodplain administrator can provide all the information on your community’s repetitive loss properties.

Element B4: All mitigation plans should document structures insured by NFIP that have been damaged repeatedly by floods. 44 CFR §201.6(c)(2)(ii)

3.) Scenario Analysis: This process can help forecast the impacts of a specific event. Scenario assessment can be particularly helpful for analyzing low-frequency high impact hazard events, for instance, earthquakes. The historical information on earthquakes is usually not available. Such assessment analyzes what would’ve happened if a specific hazard event took place, and forecasts potential impacts and losses with regard to structure casualties, monetary costs, infrastructure downtime, and loss of life. This process can even be employed to state the possible impacts, for diverse growth and development settings.

Hazus: It is FEMA approved software for loss estimation. This tool can help estimate losses for earthquake, flood, and wind hazards. Loss estimations can enumerate potential injuries, fatalities, indirect economic loss or direct property damage and loss for a specific hazard event.

Merge Risk Analysis Techniques and Available Data
A combination of risk assessment techniques will possibly be used by the mitigation planning team to state impacts, both qualitatively and quantitatively, based on the hazard event and the available data, time, personnel, and technical resources. For example, the assessment of flood risk could document the following:
• Recognition of community assets (values and numbers) located in flood-prone regions and any particular susceptibility because of the socioeconomic uses or physical traits.
• An explanation of the impact types that harmed the community assets caused by the previous flood events, for example, insured and uninsured losses and public aid expenses.
• An account of future development that may be prone to flooding based on existing zoning maps.
• Assessments of impacts including social, economic, and physical based on Hazus estimation.

The outcomes of these assessments could be included in a matrix or risk index. The function of a risk index is to evaluate hazards and grade which hazard poses the highest risk. Each hazard is assigned a grade depending on scale, likelihood, impacts, and other risk traits. A risk index isn’t a complete risk assessment but can be useful to compare multiple hazards. The mitigation plan must incorporate the analysis process and data values estimated in the risk index.

Irrespective of how the analysis techniques are used or outcomes are stated, this step should lead to a clarification of the potential impacts of each hazard on the community assets.

Updating Plan to Reveal Changes in Development

Hazard plan update should express changes in development that took place since the approval and implementation of the previous plan. The mitigation planning team will have to collect information from the building and planning divisions on the latest and planned development to appraise how susceptibility may have enhanced or lessened. Development in the hazard-prone zones and building construction not according to the updated building codes, add to the susceptibility of your community to future hazards and disasters.

The mitigation planning team may also mull over certain factors like climate changes, economic shifts, infrastructure expansion, or increasing populations that affect the community’s vulnerability. Mitigation plan updates can authenticate the information in the last approved plan if no changes in development take place or the change in development didn’t affect the overall vulnerability of the community.

Element D1: The community must assess and modify its mitigation plan to reveal changes in development. 44 CFR §201.6(d)(3)
Element B3: The risk appraisal should document an overall outline of each hazard events and its impact on your community. 44 CFR §201.6(c)(2)(ii)

Step 4: Sum-up Susceptibility

All three steps in the risk analysis process create a huge quantity of data related to potential impacts and losses, susceptible community assets, and hazards events. Such huge data or information has to be summarized for the community to comprehend and grade the most critical vulnerabilities or risks. This will help inform the mitigation strategy, as well as communicate the results to the stakeholders or elected representatives to help their decision making. The mitigation plan should document an overall outline of the vulnerabilities of each jurisdiction to the recognized hazards.
Developing problem statements is one good approach. For example, the assessments of impacts and losses can help you recognize the location of critical facilities in the hazard-prone areas, the most flood-affected regions in the past, or hazard-prone areas that are future development zones. All such concerning information can be summed-up into problem statements. Besides analyzing the hazard impacts, the planning team can create problem statements for each hazard and also recognize the issues or problems that are applicable to all hazards.

In the case of plan updates, the problem statements need to be revised to echo the existing risk evaluation. The process may involve creating new statements, as well as revising or deleting those that are no longer applicable since mitigation plans have included the risks or scenarios that have changed.